Minnesota's new get-tough approach to charter schools dealt blows to several organizations by denying their requests to continue supervising more than 30 of the schools.

Now the organizations have until next Thursday to provide more information and ask state officials to reconsider.

While most said they intend to gain final approval, the episode underscores both the state's determination to hold those supervising agencies accountable for meeting higher standards, and the real-life difficulty of raising educational achievement in disadvantaged communities.

Last month, the Minnesota Department of Education rejected seven of 13 applications from organizations seeking to become charter school "authorizers" under a new law. Authorizers have primary authority and responsibility to oversee the schools' financial and educational operations.

The law resulted from a string of media reports in the Star Tribune and elsewhere about academically failing and financially mismanaged charter schools. In their rejection letters to the hopeful authorizers, state officials consistently underscored the need for clearer academic and financial accountability between schools and the authorizers.

Minnesota has a total of 52 such organizations that supervise 152 charter schools with 33,000 students. All of the supervisory organizations must reapply with the state over the next two years.

Perhaps none is more problematic than Pillsbury United Communities, a century-old, Minneapolis nonprofit dedicated to working with low-income communities that in the past decade has taken responsibility for sponsoring 13 charter schools. Education Department officials denied the organization's initial request to continue authorizing charter schools.

"Clearly we were disappointed," said Tony Wagner, the nonprofit's president. "We've invested a lot of time and energy and goodwill into trying to do what we can to make the charter system work." Pillsbury plans to address the concerns raised by education officials in their denial notice, Wagner said.

Statewide test scores continue to place some charter schools among the worst performers, while others are reaping promising rewards. For example, Pillsbury's Sojourner Truth elementary school in north Minneapolis recorded an impressive 16 percent gain in math and a 6 percent gain in reading last year, while 42 percent of students met or exceeded state standards, beating out nearby Minneapolis public schools.

But Pillsbury also sponsors the High School for Recording Arts in St. Paul, where only 5 percent of the students scored proficient on their math exam last year, compared with 12 percent in 2008 and 0 percent in the prior year.

"Clearly, all of us want to have kids better educated than our collective response has yielded in the past," Wagner said. But he also cautioned against comparing the educational achievements of children who are homeless or highly mobile and live in unstable families -- as are many students in the schools that Pillsbury sponsors -- with those in more nurturing and higher income settings.

"I'm not blaming anyone. It is what it is. You have to start somewhere with higher standards," Wagner said. "I'm just hoping that our responses can lead to a better understanding of this process as to what can be achieved here."

If the schools' current sponsors are not approved as authorizers, charter schools must find sponsors among approved organizations or close.

State officials, who earlier absorbed criticism for being too lenient with charter schools and recently for being heavy-handed, declined to comment on their recent actions. They've decided to withhold comment until the deadline passes for the organizations to submit revised proposals.